> social security, pensions, and lump-sum savings

Isn't that very little money?

In short, yes, but my family is very cheap, so it is doable with sacrifice. I think I'm middle class (or maybe upper-middle?) now, but I think I'm the first generation that can say that. And even I rented closets, garages, and spaces behind TV's until about 4 years ago, lol.

While defined-benefit pensions are less and less common, they may not be small.